Cluster-randomized trials of cancer screening interventions: Has use of appropriate statistical methods increased over time?

BACKGROUND

In a cluster randomized trial, groups of individuals (e.g., clinics, schools) are randomized to conditions. The design and analysis of cluster randomized trials can require more care than individually randomized trials. Past reviews have noted deficiencies in the use of appropriate statistical methods for such trials.

METHODS

We reviewed cluster randomized trials of cancer screening interventions published 1995-2019 to determine whether appropriate statistical methods had been used for sample size calculation and outcome analysis and whether they reported intraclass correlation coefficient (ICC) values. This work expanded a previous review of articles published 1995-2010.

RESULTS

Our search identified 88 articles published 1995-2020 that reported outcomes of cluster randomized trials of breast, cervix, and colorectal cancer screening interventions. There was increased reporting of the trials' sample size calculations over time, with the percentage increasing from 31% in 1995-2004 to 77% in 2014-2019. However, the percentage of calculations failing to account for cluster randomization did not change over time and was 17% of studies in 2014-2019. There was a nonsignificant trend towards increased use of outcome analysis methods that accounted for the cluster randomized design. However, in lower impact journals, use of appropriate analysis methods was only 80% in 2014-2019. Only 33% of studies reported ICC values in 2014-2019.

CONCLUSION

For cluster randomized trials with cancer screening outcomes, there have been improvements in the reporting of sample size calculations but methodological and reporting deficiencies persist. Efforts to disseminate, adopt and report the use of appropriate statistical methodologies are still needed.

Effectiveness of behavioural economics-based interventions to improve colorectal cancer screening participation: A rapid systematic review of randomised controlled trials

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We searched PubMed, PsycInfo and EconLit for RCTs that evaluated BE interventions in CRC screening.

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We identified 1027 papers for title and abstract review. 30 studies were eligible for the review.

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The most frequently tested BE intervention was incentives, followed by default principle and salience.

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Default-based interventions were most likely to be effective. Incentives had mixed evidence.

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BE remains a promising field of interest in relation to influencing CRC screening behaviours.

Two randomized controlled trials for colorectal cancer screening invitations developed using a behavioral science approach

The effectiveness of behaviorally informed, targeted invitations to standard invitations and to no invitation (control arm, primary analysis) were compared in the context of an organized colorectal cancer (CRC) screening program. Two multi-arm, pragmatic randomized controlled trials in men (arms: male-specific, unisex, standard invitation, or no invitation) and in women (arms: unisex, standard invitation, or no invitation), were conducted in Ontario, Canada. Eligible persons aged 50-74, due for CRC screening, were randomized. Primary and secondary outcomes were completion of the guaiac fecal occult blood test (gFOBT) and uptake of any colorectal test, respectively, within 5 months of mailing. Impact of invitation type was assessed using logistic regression. Letters were mailed to 75,810 men and women; 38,673 males and 34,453 females were included in the analyses. Men who received the male-specific letter were most likely to screen with gFOBT compared to controls (odds ratio (OR) 7·24, 95% CI: 5·77, 9·09), followed by those receiving the unisex letter (OR 6·75, 95% CI: 5·37, 8·47) and the standard letter (OR 5·99, 95% CI: 4·76, 7·53). Women who received the unisex letter were most likely to be screened with gFOBT compared to controls (OR 7·07, 95% CI: 5·83, 8·59), followed by those receiving the standard letter (OR 6·76, 95% CI: 5·56, 8·21). In both trials, the findings were similar for the secondary outcome. Mailed invitations were effective for both men and women. With greater targeting using the behaviorally informed invitations, the magnitude of benefit relative to no invitation appeared to increase. (ClinicalTrials.gov, NCT02364895).

Colorectal cancer and potential predictors of never screened for faecal occult blood test: a narrative review

Colorectal cancer (CRC) is a major public health threat. Therefore, CRC screening uptake has been a focus with the established precancerous lesion and the strong association of early detection with staging and survival of the disease. However, CRC screening is relatively low in many countries. This article briefly discussed the current situation of CRC, recommendations, and current uptake of CRC screening in various countries. Besides that, this article also highlights the potential factors that help to predict the CRC screening uptake worldwide. Identification of those factors could guide policymakers to develop an effective strategy to improve the CRC screening uptake and ultimately improve the health outcome of the population.

Text Messaging and Opt-out Mailed Outreach in Colorectal Cancer Screening: a Randomized Clinical Trial

BACKGROUND

Routine screening reduces colorectal cancer mortality, but screening rates fall below national targets and are particularly low in underserved populations.

OBJECTIVE

To compare the effectiveness of a single text message outreach to serial text messaging and mailed fecal home test kits on colorectal cancer screening rates.

DESIGN

A two-armed randomized clinical trial.

PARTICIPANTS

An urban community health center in Philadelphia. Adults aged 50-74 who were due for colorectal cancer screening had at least one visit to the practice in the previously year, and had a cell phone number recorded.

INTERVENTIONS

Participants were randomized (1:1 ratio). Individuals in the control arm were sent a simple text message reminder as per usual practice. Those in the intervention arm were sent a pre-alert text message offering the options to opt-out of receiving a mailed fecal immunochemical test (FIT) kit, followed by up to three behaviorally informed text message reminders.

MAIN MEASURES

The primary outcome was participation in colorectal cancer screening at 12 weeks. The secondary outcome was the FIT kit return rate at 12 weeks.

KEY RESULTS

Four hundred forty participants were included. The mean age was 57.4 years (SD ± 6.1). 63.4% were women, 87.7% were Black, 19.1% were uninsured, and 49.6% were Medicaid beneficiaries. At 12 weeks, there was an absolute 17.3 percentage point increase in colorectal cancer screening in the intervention arm (19.6%), compared to the control arm (2.3%, p < 0.001). There was an absolute 17.7 percentage point increase in FIT kit return in the intervention arm (19.1%) compared to the control arm (1.4%, p < 0.001).

CONCLUSIONS

Serial text messaging with opt-out mailed FIT kit outreach can substantially improve colorectal cancer screening rates in an underserved population.

TRIAL REGISTRATION

clinicaltrials.gov ( https://clinicaltrials.gov/ct2/show/NCT03479645 ).

Factors of Never Screened with Faecal Occult Blood Test in Public Primary Care Facilities

BACKGROUND

Colorectal cancer (CRC) is still a major public health threat. In the effort to reduce CRC incidence and mortality, faecal occult blood test (FOBT) is currently the screening tools used for early detection of CRC. However, the uptake of FOBT screening is less than promising. This study aims to identify the prevalence and predictors of Never Screened with FOBT (NS-FOBT).

METHODS

A cross sectional study was conducted in five health clinics under Kota Kinabalu district, Sabah, Malaysia Borneo involving 162 attendees with age of 50 years old and above. A validated self-administered questionnaire was used to collect the data. Multiple logistic regression analysis was used to determine the predictors of NS-FOBT.

RESULTS

The prevalence of NS-FOBT was 85.8% (n=139). Important predictors of NS-FOBT were age (aOR: 0.922; 95% CI: 0.855, 0.995; p=0.035), Bumiputera ethnicity (vs Non Bumiputera; aOR: 4.285; 95% CI: 1.384, 13.263; p=0.012), knowledge score (aOR: 0.921; 95% CI: 0.856, 0.99; p=0.027), and attitude score (aOR: 0.801; 95% CI: 0.702, 0.913; p=0.001).

CONCLUSION

There is high prevalence of NS-FOBT. Age, ethnicity, knowledge, and attitude were important predictors of NS-FOBT. Strategies are needed to improve FOBT screening rate among the public. Socio-culturally tailored health promotion strategies as well as strengthening the communication, collaboration, and education to enhance the role of family physician is vital in improving the CRC prevention and care.

Impact of the introduction of a new policy of direct faecal immunochemical home screening test provision in a national bowel screening programme, both during and outside of advertising campaigns

BACKGROUND

BowelScreen, The National Bowel Screening Programme in Ireland, offers free colorectal screening to persons aged 60-69 through a home Faecal Immunochemical Test (FIT) kit. 40.2% uptake in the first screening round was below the programme standard (≥50.0%). To improve uptake, an intervention saw FIT kits sent directly to previously screened clients rather than by the usual invitation process comprising a letter of invitation followed by a FIT kit if requested. The intervention proved successful and was fully implemented into the programme for subsequent clients. Despite the improved uptake it was noted over time that the unsatisfactory FIT rate was approaching the programme standard (≤3%). The aim of this study is to compare uptake by two invite methods occurring contemporaneously alongside advertising and to compare unsatisfactory rates before and after full FIT-Direct implementation.

METHODS

Percentage uptake and 95% confidence intervals (CI) were calculated for each invite method before and after advertising and compared using two-proportion z-tests. Rate ratios and 95% CI compared the unsatisfactory FIT rate before and after full-FIT Direct implementation.

RESULTS

Uptake was significantly higher amongst FIT-Direct compared with Usual-Invite clients during (91.0% vs 84.9%, p < 0.0001) and outside advertising (93.8% vs 85.3%, p < 0.0001). The unsatisfactory FIT rate was 2.3 times higher (95% CI: 1.84-2.92, p < 0.0001) after full FIT-Direct implementation compared with before.

CONCLUSIONS

The FIT-Direct intervention had an overall positive effect on uptake. After adjusting for advertising, uptake of FIT was higher outside advertising periods. Monitoring of the unsatisfactory rate is ongoing; a communication enhancement strategy may be required should this persist.

Decreased Colorectal Cancer Incidence and Incidence-Based Mortality in the Screening-Age Population of Ontario

Background and Aims

We aimed to evaluate trends in Ontario, Canada, 2002 to 2016, in uptake of colorectal evaluative procedures, colorectal cancer (CRC) incidence and incidence-based mortality in the colorectal screening-age population.

Methods

We defined the screening age-eligible population as persons 51 to 74 years of age with ≥1 year eligibility for the Ontario Health Insurance Plan, excluding those with a diagnosis of CRC in the Ontario Cancer Registry (OCR) prior to age 50 or January 1, 2002. We computed annual up-to-date status with colorectal evaluative procedures from billing claims, and CRC incidence from the OCR. In order to compute incidence-based CRC mortality, we included persons with a first diagnosis of CRC between the ages of 51 and 74, diagnosed between January 1, 1992 and December 31, 2001, still alive and <75 years of age on January 1, 2002, based on cause of death from the OCR. Overall, age-stratified and sex-stratified trends were evaluated by Cochran–Armitage trend tests.

Results

Persons up to date with colorectal evaluative procedures increased from 628,214/2,782,061 (22.6%) in 2002 to 2,584,570/4,179,789 (62.2%) in 2016. CRC incidence fell from 129.3/100,000 in 2002 to 94.54/100,000 in 2016, and incidence-based CRC mortality fell from 40.8/100,000 to 24.1/100,000. Decreasing trends in overall and stratified incidence and mortality were all significant, except among persons 51 to 54 years old.

Conclusions

There was continued increase in persons up-to-date with colorectal evaluative procedures, and significant decrease in CRC incidence and incidence-based CRC mortality from 2002 through 2016.

Directly Mailing gFOBT Kits to Previous Responders Being Recalled for Colorectal Cancer Screening Increases Participation

Background

Colorectal cancer (CRC) screening with guaiac fecal occult blood test (gFOBT) reduces CRC-related death. Average risk individuals should be recalled for screening with gFOBT every 2 years in order to maximize effectiveness. However, adherence with repeated testing is often suboptimal. Our aim was to evaluate whether adding a gFOBT kit to a mailed recall letter improves participation compared with a mailed recall letter alone, among previous responders to a mailed invitation.

Methods

We conducted a cluster randomized controlled trial, with the primary care provider as the unit of randomization. Eligible patients had completed a gFOBT and tested negative in an earlier pilot study and were now due for recall. The intervention group received a mailed CRC screening recall letter from their primary care provider plus a gFOBT kit (n = 431) while the control group received a mailed CRC screening mailed recall letter alone (n = 452). The primary outcome was the uptake of gFOBT or colonoscopy within 6 months.

Results

gFOBT uptake was higher in the intervention group (61.3%, n = 264) compared with the control group (50.4%, n = 228) with an absolute difference between the two groups of 10.8% (95% confidence interval [CI]: 1.4 to 20.2%, P = <0.01). Patients in the intervention group were more likely to complete the gFOBT compared with the control group (odds ratio [OR] = 1.4; 95% CI: 1.1 to 1.9).

Conclusion

Our findings show that adding gFOBT kits to the mailed recall letter increased participation among persons recalled for screening. Nine gFOBT kits would have to be sent by mail in order to screen one additional person.

Improving proteinuria screening with mailed smartphone urinalysis testing in previously unscreened patients with hypertension: a randomized controlled trial

BACKGROUND

Proteinuria screening is recommended for patients with hypertension to screen for kidney disease and identify those at elevated risk for cardiovascular disease. However, screening rates among hypertensive patients are low. Home testing strategies may be useful in improving proteinuria screening adherence.

METHODS

We conducted an individual-level, randomized trial at 55 primary care clinic sites in the Geisinger Health System to evaluate the effectiveness of a strategy using home smartphone urinalysis test (Dip.io) to complete proteinuria screening in previously unscreened non-diabetic patient portal users with hypertension. All patients received an educational letter and a standing urinalysis lab order, and then were randomized to control (usual care) or intervention. Intervention arm participants were invited to complete proteinuria screening with a mailed home smartphone urinalysis test. Co-primary outcomes were completion of proteinuria screening and number of albuminuria cases (albumin/creatinine ratio [ACR] ≥ 30 mg/g or protein/creatinine ratio ≥ 150 mg/g) at the end of 3 months. We also evaluated patient satisfaction with the home test, and compliance with recommendations for patients with newly detected albuminuria.

RESULTS

A total of 999 patients were randomized to intervention or control. Out of 499 patients assigned to the intervention arm, 253 were reached by phone, and 69/97 (71.1%) consented patients completed the home test. Overall, the intervention increased proteinuria screening completion (28.9% vs. 18.0%; p < 0.001) with no effect on the number of albuminuria cases (4 vs. 4) although only 6/57 (10.5%) patients with trace or 1+ urine dipstick protein had a follow-up quantitative test. Among the 55 patients who completed a survey after the home test, 89% preferred testing at home rather than the physician's office.

CONCLUSIONS

A strategy using a home urinalysis smartphone test increased proteinuria screening rates in previously unscreened patients with hypertension and may be useful in increasing rates of proteinuria screening compliance. Future studies should evaluate use of home testing kits to screen for and confirm albuminuria, and determine whether improving early detection of kidney disease can improve future kidney health.

TRIAL REGISTRATION

Clinical Trial Registry: NCT03470701 (First posted 3/20/2018) https://clinicaltrials.gov/ct2/show/NCT03470701 . This study was retrospectively registered.

Effectiveness of reminder strategies on cancer screening adherence: a randomised controlled trial

BACKGROUND

Few randomised controlled trials (RCTs) have evaluated the different recalling approaches for enhancing adherence to faecal immunochemical test (FIT)-based screening.

AIM

The authors evaluated the effectiveness of two telecommunication strategies on improving adherence to yearly FIT screening.

DESIGN AND SETTING

A randomised, parallel group trial was performed in a primary care screening practice.

METHOD

The authors recruited 629 asymptomatic individuals aged 40-70 years with a negative FIT in 2015 to a population-based screening programme. On participation, they were invited to repeat their second round of FIT in 2016, 12 months after the first test. Each participant was randomly assigned to either interactive telephone reminder (n = 207), short message service reminder (SMS, n = 212), or control, where no additional interventions were delivered after the findings of their first FIT was communicated to the participants (n = 210). Reminders in the intervention groups were delivered 1 month before subjects' expected return. Additional telephone reminders were delivered 2 months after the expected return date to all subjects who defaulted specimen return. The outcomes included rates of FIT collection and specimen return up to 6 months after their expected return.

RESULTS

At 6 months, the cumulative FIT collection rate was 95.1%, 90.4%, and 86.5%, respectively, for the telephone, SMS, and control groups (P = 0.010). The corresponding specimen return rate was 94.1%, 90.0%, and 86.0% (P = 0.022). When compared with the control, only subjects in the telephone group were significantly more likely to collect FIT tubes (adjusted odds ratio [AOR] 3.18, 95% confidence interval [CI] = 1.50 to 6.75, P = 0.003) and return completed specimens (AOR = 2.73, 95% CI = 1.35 to 5.53, P = 0.005).

CONCLUSION

Interactive telephone reminders are effective at securing previously screened subjects to repeat screening 1 year after a negative finding.

Predictors of non-adherence to colorectal cancer screening among immigrants to Ontario, Canada: a population-based study

Though colorectal cancer (CRC) screening rates have increased over time in Ontario, Canada, immigrants continue to have lower rates of screening. This study examines the association between non-adherence to CRC screening and immigration, socio-demographic, healthcare utilization, and primary care physician characteristics among immigrants to Ontario. This is a population-based retrospective cross-sectional study that uses healthcare administrative databases housed at the Institute for Clinical Evaluative Sciences. Our cohort comprised immigrants aged 60 to 74 years who lived in Ontario on March 31, 2015 and who had been eligible for the Ontario Health Insurance Plan for at least 10 years. The outcome was lack of adherence to CRC screening with any modality (fecal occult blood test, flexible sigmoidoscopy, colonoscopy) on March 31, 2015. Our cohort contained 182,949 immigrants. Overall 70,134 (38%) individuals were not adherent to screening. Risk of non-adherence to CRC screening was higher among immigrants who were from low (adjusted relative risk [ARR] 1.35, 95%CI 1.28-1.42) or low-middle (ARR 1.27, 95%CI 1.24-1.30, population-attributable risk [PAR] 9.8%) income countries and refugees (ARR 1.09, 95%CI 1.06-1.11). Compared to those from the United States, Australia, and New Zealand, immigrants from most other world regions, particularly Eastern Europe and Central Asia (ARR 1.28, 95%CI 1.21-1.37), had higher risks of non-adherence. Non-immigration factors such as low healthcare use and lack of primary care enrolment also increased the risk of non-adherence to screening. These findings can be used to inform future efforts to improve uptake of CRC screening among immigrant groups.

Adherence to colorectal cancer screening: four rounds of faecal immunochemical test-based screening

BACKGROUND

The effectiveness of faecal immunochemical test (FIT)-based screening programs is highly dependent on consistent participation over multiple rounds. We evaluated adherence to FIT screening over four rounds and aimed to identify determinants of participation behaviour.

METHODS

A total of 23 339 randomly selected asymptomatic persons aged 50-74 years were invited for biennial FIT-based colorectal cancer screening between 2006 and 2014. All were invited for every consecutive round, except for those who had moved out of the area, passed the upper age limit, or had tested positive in a previous screening round. A reminder letter was sent to non-responders. We calculated participation rates per round, response rates to a reminder letter, and differences in participation between subgroups defined by age, sex, and socioeconomic status (SES).

RESULTS

Over the four rounds, participation rates increased significantly, from 60% (95% CI 60-61), 60% (95% CI 59-60), 62% (95% CI 61-63) to 63% (95% CI 62-64; P for trend<0.001) with significantly higher participation rates in women in all rounds (P<0.001). Of the 17 312 invitees eligible for at least two rounds of FIT screening, 12 455 (72%) participated at least once, whereas 4857 (28%) never participated; 8271 (48%) attended all rounds when eligible. Consistent participation was associated with older age, female sex, and higher SES. Offering a reminder letter after the initial invite in the first round increased uptake with 12%; in subsequent screening rounds this resulted in an additional uptake of up to 10%.

CONCLUSIONS

In four rounds of a pilot biennial FIT-screening program, we observed a consistently high and increasing participation rate, whereas sending reminders remain effective. The substantial proportion of inconsistent participants suggests the existence of incidental barriers to participation, which, if possible, should be identified and removed.

Rapid review of evaluation of interventions to improve participation in cancer screening services

Objective

Screening participation is spread differently across populations, according to factors such as ethnicity or socioeconomic status. We here review the current evidence on effects of interventions to improve cancer screening participation, focussing in particular on effects in underserved populations.

Methods

We selected studies to review based on their characteristics: focussing on population screening programmes, showing a quantitative estimate of the effect of the intervention, and published since 1990. To determine eligibility for our purposes, we first reviewed titles, then abstracts, and finally the full paper. We started with a narrow search and expanded this until the search yielded eligible papers on title review which were less than 1% of the total. We classified the eligible studies by intervention type and by the cancer for which they screened, while looking to identify effects in any inequality dimension.

Results

The 68 papers included in our review reported on 71 intervention studies. Of the interventions, 58 had significant positive effects on increasing participation, with increase rates of the order of 2%–20% (in absolute terms).

Conclusions

Across different countries and health systems, a number of interventions were found more consistently to improve participation in cancer screening, including in underserved populations: pre-screening reminders, general practitioner endorsement, more personalized reminders for non-participants, and more acceptable screening tests in bowel and cervical screening.

Optimising colorectal cancer screening acceptance: a review

The study aims to review available evidence concerning effective interventions to increase colorectal cancer (CRC) screening acceptance. We performed a literature search of randomised trials designed to increase individuals' use of CRC screening on PubMed, Embase, Cochrane Database of Systematic Reviews and Database of Abstracts of Reviews of Effects. Small (≤ 100 subjects per arm) studies and those reporting results of interventions implemented before publication of the large faecal occult blood test trials were excluded. Interventions were categorised following the Continuum of Cancer Care and the PRECEDE-PROCEED models and studies were grouped by screening model (opportunistic vs organised). Multifactor interventions targeting multiple levels of care and considering factors outside the individual clinician control, represent the most effective strategy to enhance CRC screening acceptance. Removing financial barriers, implementing methods allowing a systematic contact of the whole target population, using personal invitation letters, preferably signed by the reference care provider, and reminders mailed to all non-attendees are highly effective in enhancing CRC screening acceptance. Physician reminders may support the diffusion of screening, but they can be effective only for individuals who have access to and make use of healthcare services. Educational interventions for patients and providers are effective, but the implementation of organisational measures may be necessary to favour their impact. Available evidence indicates that organised programmes allow to achieve an extensive coverage and to enhance equity of access, while maximising the health impact of screening. They provide at the same time an infrastructure allowing to achieve a more favourable cost-effectiveness profile of potentially effective strategies, which would not be sustainable in opportunistic settings.